The use of a composite (e.g., organic polymer resin) in an air vehicle (e.g., aircraft or missile) control surface is desirable because the composite can provide adequate strength and stiffness at a lower weight than metals. However, the use of such composites is limited by the composite's maximum use temperature. For example, when a composite's resin glass transition temperature (Tg) is exceeded, the composite can char or burn, rapidly diminishing the properties of the composite and compromising the composite's structural integrity.
Current composites (e.g., organic polymer resins) are capable of surviving sustained use temperatures of up to about 650 F and can survive short exposure to much higher temperatures. However, as flight speeds of air vehicles continue to increase, the temperatures induced by air friction on the composite's control surface exceed the composite's Tg. Therefore, a conventional belief is that composites materials are not a viable option in high speed, high thermal loading environments.